Okay, watching through, writing comments as I go so sorry if this feels a bit disjointed.
You could have won the first missile if you had moved your harvester onto the bottom left platform while you were waiting for a counter to arrive, always important to remember that harvesters hold platforms better than most anything else in the game in a pinch.
You should have gone after the other harvester with your attack trikes, forced them to devote resources there; throwing them away definitely was not great. Also given the narrow chokes on this map and the fact they were making infantry you probably should have gone for a rifleman or flame trooper over the second trike, one moving between the two harvesters is going to force them to commit to both spots anyway giving you a slight tempo lead.
There is a point near the end where you lose a flame tank unnecessarily, had you targeted the obelisk instead of their flame tank you'd have been fine. (though it was hardly relevant at this point)
On a side note if you're going to run flame troopers get them above level 3 :P 1 level differences don't matter that much but 3 level differences sure do, I'm fairly willing to bet they could have spammed riflemen prior to you getting flame tanks and come out ahead.
One other thing, you seem hesitant to move units off of the platforms once they are there, if the missile isn't near firing and that unit can go and counter something somewhere (like the one laser trooper you suicided your trikes into for instance) go do that, holding the platforms at 10% missile charge isn't going to help you win the game very often when you aren't in the lead.
Otherwise, mostly just small mistakes here and there, nothing too major, a lot of it is just getting the micro down, remembering all of your options, and leveling up your flame troopers :P
